Electric timer

ABSTRACT

An electric timer for measuring predetermined time intervals to which the timer can be manually set. The timer includes a motordriven main timing shaft equipped with an indicator hand moved by the shaft about a calibrated face subdivided into time intervals. The shaft is equipped with a knob to facilitate manual positioning of the hand at any selected time interval, and the timer is placed in operation by manual displacement of such knob, shaft, and hand from a zero time position into any time-measuring calibration. A light providing a visual indicator is included, and it is energized concurrently with the timer motor to provide indicia that the timer is in operation. A buzzer or other audible indicator is also included, and it becomes operative at a predetermine instant in any timing interval being measured to provide indicia that the timing cycle has been or is nearing completion. The timer is arranged so that both the visual and audible indicators are energized concurrently for a brief interval of predetermined duration, and all of the various states of the timer are generally responsive to and determined by the condition of a main control switch which is sequentially changed from a normal-run, to an alarm-run, and then to a non-run condition in accordance with predetermined angular position of the timing shaft during a timing cycle.

[151 3,663,830 [451 May 16,1972

[54] ELECTRIC TIMER Clifford E. Miller, 5307 East 14th St., Oakland, Calif. 94601 [22] Filed: June 29,1970

[21] Appl.No.: 50,457

[72] Inventor:

[52] US. Cl. ..307/141, 200/38 A [51] Int. Cl. ..l-l0lh 43/14 [58] Field ofSearch ..200/38,38 A; 307/141, 141.4; 317/141 [56] References Cited UNITED STATES PATENTS 3,205,379 9/ 1 965 Lundin ..307/41 3,094,593 6/1963 Bowman 200/38 A 3,190,976 6/1965 Ellis et al. 200/38 A 3,348,008 10/1967 Miller ..307/141 3,359,382 12/1967 'l-lendry..." 307/141 X 3,391,258 7/1968 Virnoche ..200/38 3,454,730 7/1969 Miller ..200/38 Primary Examiner-Robert K. Schaefer Assistant Examiner-William J. Smith Attorney-Joseph B. Gardner [5 7] ABSTRACT An electric timer for measuring predetermined time intervals to which the timer can be manually set. The timer includes a motor-driven main timing shaft equipped with an indicator hand moved by the shaft about a calibrated face subdivided into time intervals. The shaft is equipped with a knob to facilitate manual positioning of the hand at any selected time interval, and the timer is placed in operation by manual displacement of such knob, shaft, and hand from a zero time position into any time-measuring calibration. A light providing a visual indicator is included, and it is energized concurrently with the timer motor to provide indicia that the timer is in operation. A buzzer or other audible indicator is also included, and it becomes operative at a predetermine instant in any timing interval being measured to provide indicia that the timing cycle has been or is nearing completion. The timer is arranged so that both the visual and audible indicators are energized concurrently for a brief interval of predetermined duration, and all of the various states of the timer are generally responsive to and determined by the condition of a main control switch which is sequentially changed from a normal-run, to an alarm-run, and then to a non-run condition in accordance with predetermined angular position of the timing shaft during a timing cycle.

6 Claims, 6 Drawing Figures IIOVAC L l Patented May 16,- 1972 3,663,830

4 INVENTOR:

(L/FFORD E. MILLER Wfi 40 ,0

A TTORNEY tion. Additionally, and anindicator hand. movable ,thcreover which can be examples thereof are found in my 'prior US. Pat. Nos.

3,348,008 and 3,454,730. Such timers commonly-have lights providing a visual indication of the condition of the timer, the light usually being energized whenever the timer is in operasuch timers have a calibrated dialor face manually set to establish the duration of any time interval to be measured by the mechanism. Further, the timer disclosed in my aforementioned U.S. Pat. No. 3,454,730 includes an audible indicator energized at the termination of the timing cycle to alert'appropriate personnel that the cycle has ended. Thus, by glancing at the timer one knows whether it is. in operation by the condition of the indicator light, is apprised of the length of time remaining during any timing interval by the position of the indicatorhand, and is alerted to the expiration of any timing cycle by actuation of an audible indicator.

, in certain instances, however, the time at which some function is to be manually performed is critical and as a consequence, any delay between the expiration of the time interval measured by the timing mechanism and the momentat which such function is performed could be exceedingly disad- .vantageous. Examples of such instancesare various types of scientific experiments, certain cooking operations such as electronic cooking of poultry, etc. ln-view of these conditions of-criticality a general object, among others, of the presentinvention is to provide a timer the use of which willztend to'obviate such disadvantageous occurrences.

Another object of the-invention; is that of providing an improved electric timer of the type described which has first'and second-indicators, thefirst'thereof being a visual indicator energized wheneverthe timer is in operation toprovide indicia representative of that conditionand the second being an audible, indicator energized at a predetermined point in the timing interval being measured, usually quite close to zero time or the end of the timing interval, to alert, personnel to the fact. such-point has been reached, both of the indicators then remaining energized concurrently fromthe instant that the audible indicator is actuated until the termination of the timing interval at which the visual indicator is deenergized but the audibleindicator remains in operation until manual intervention terminates the same. As a result of such concurrent operation of the visual andaudible indicators for a time period of predetermined duration, personnel are apprised as to whether time remains in which to perform the functions intended or whether the critical time has been reached and passed.

A further object is in the: provision ofanimproved-zelectric timer of the character described which-has'a multiple-contact main control switch having normal-run, alarm-run, and nonrun conditions controlling various phases in the operational cycle of the timer, the switch being sequenced through'the various conditions thereof in response to the angular position of a motor-driven timing control shaft forming a part of the timer mechanism.

Yet a further object is to provide electric timing mechanism in-which the main control switch is sequenced through the various conditions thereof by coaction therewith of time control structure in the form of an arm operative in enforced synchronism with the motor-driven timing shaft, in which the timer is placed in operation simply by manually positioning the timing shaft and indicator hand mounted thereon at the desired setting with the result that no separate manually operable on-off switch is required, in which the operating 75 :15 (FIG. 2)'driven byan electric motor 16 cycle of the timer is tenninated by movement ofthe main control switch into the non-run position thereof whereby no separate time-controlled shut-off switch is necessary, in which stop means are includedto positively establish thezero time position of the timer, and in which frictional inhibition means are included in association with the timecontrol structure to resist inadvertant displacements .thereof away from such stop so as to prevent accidental and unwanted energizations of the timer.

Additional objects and advantages of the invention, especially as concerns particular features and characteristics thereof, will become apparent as the specification continues.

An embodiment of the invention is illustrated in the accompanying drawing, in which:

FIG. 1 is a front view in elevation of a timer embodying the present invention;

. FIG. 2 is a side view in elevation of the timer shown in FIG.

FIG. 3 is an enlarged, broken rear view in elevation illustrating details of the timing switch and motor driven control therefor, and showing the switch in the alarm-run condition thereof;

FIGS. 3A and 3B are broken rear views in elevation similar to that of FIG. Sand respectively illustrating the normal-run and non-run conditions of the switch which are not shown in FIG. 3; and

FIG. 4 is a schematic circuit diagram of the timer.

Timer mechanism embodying the present invention includes a suitable casing having a front panel 10, the side and rear walls of the casing being removed for clarity. Mounted upon the front panel 10, is a numbered face 11 that may be covered with a transparent crystal or window 12 releasably heldin position byan annular clamp ring removably secured to the panel 10 by a plurality of cap screws, as shown in FIG. 1. The numbers on the dial or facell indicate time intervals, and inthe embodiment of the invention illustrated, the face is subdivided intoprimary time intervals of 2 minutes, 4 minutes,

6 minutes,and 8 minutes (the latter being the time required for the sweep or indicator hand 14 to make one complete 360 rotation). The hand 14 is constrained upon a main timing shaft through a gear train generally denoted with the numeral 17. The motor 16 and gear train.l7 may be standard clock mechanism, such as that sold underthe trademark Synehron, and no further description thereof will be include As viewed in FIG. 1, the timing shaft 15 and indicator hand 14 mounted thereon are driven in a clockwise direction whenever the motor 16 is energized. The hand 14 is manually displacable from the zero position shown by a knob 18 mounted upon the shaft 15 in a manner preventing relative rotation therebetween. Thus, if it is desired to have the timer alert one to the elapse'of a time interval of 2 minutes, the knob 18 is manually displaced in a counterclockwise direction to position the hand 14 in alignment with the 2-minute marker. Such displacement of the hand 14 will energize the motor 16, as hereinafter described in detail, so that the hand will be returned to the zero position illustrated after a period of 2 minutes has passed. Similarly, the indicator hand 14 is set on the numeral 4 or 4-minute marker if the timing interval is to be a 4-minute period, it is set on 6-minute marker if the interval is to be 6 minutes, etc. It will be appreciated that the gear train 17 in association with the motor l6'is designed so that one complete rotation of the shaft 15 is equal to a time interval of 8 minutes, but other timing intervals are readily provided should this be desired.

Also, supported along the front panel 10 is a first indicator in the form of an electric signal lamp or light 19 (actually enclosed in a transparent shield or cover which may be colored to attract attention thereto) that provides visual indicia that the timer mechanism is in operation. A second indicator in the form of an electric buzzer or vibrator 20 is also mounted upon the front panel 10 to provide audible indicia that the timing cycle has reached a predetermined condition. lfdesired, such buzzer may be adjustable so that the sound level thereof can be varied to suit environmental requirements and the audible sensitivity of the person to be alerted by the buzzer. The buzzer 20 is connected in circuit with a buzzer or alarm control switch 21 mounted upon a somewhat U-shaped bracket 22 secured to the front panel and extend rearwardly therefrom, as seen best in FIG. 2. The switch 21 is normally open, as shown in the drawing, and is under the control of a solenoid so as to be opened thereby.

The solenoid control for the switch 21 includes an energizing coil 23 carried by the bracket 22 adjacent the face plate 10, and a reciprocable plunger 24 passing through the energizing coil 23 and equipped at the outer end thereof with a knob 25 to facilitate manual manipulation thereof. At its inner end, the plunger 24 is adapted to extend between the two contacts of the switch 21 so as to maintain the same in their open position. Upon energization of the solenoid coil 23 the plunger 24 is displaced toward the right, as viewed in FIG. 2, to release the movable contacts of the switch 21 which, because they are resiliently biased toward their closed position, then move together to close and thereby complete the buzzer circuit, as will become evident hereinafter.

Disposed in spaced parallel relation with the front panel 10 rearwardly thereof is a mountingplate 26 which is held in such position by a plurality of angularly separated posts 27. Mounted upon the plate 26 is a multiple-contact timing or main control switch 28 selectively movable into the positions respectively illustrated in FIGS. 3A and 3 and 3B. The switch 28 has three contact arms respectively denoted with the numerals 29, 30, and 31; the intermediate arm 30 of which is substantially longer than the other two arms and is adapted to cooperate with time control structure in the form of a control arm 32 having a post 34 thereon adapted to engage the contact 30 during certain stages of the timing cycle, as shown in FIG. 3 and 3B. The control arm is mounted upon the shaft so as to rotate in enforced synchronism therewith, and it generally is in positional alignment with the indicator hand 14, although such relative positioning is not required. A stop or abutment 35 extending rearwardly from the front panel 10 and supported thereby is adapted to be engaged by the control arm 32, as shown in FIG. 3B, and defines the maximum angular displacement of the shaft 15, indicator hand 14 and control arm 32 in a clockwise direction, as viewed in FIG. 1 (i.e., counterclockwise direction as viewed in 3, 3A and 3B).

The condition of the switch 28 is directly dependent upon and controlled by the angular orientation of the control arm 32 and post 34 carried thereby. Thus, when the arm 32 and post 34 are remote from the elongated center contact 30 of the switch 28, as shown in FIG. 3A, the inherent resilience of the contact arms 29 and 30 cause the same to close while at this time the natural relative positions of the switch arms 30 and 31 cause the contacts thereof to be open. This condition of the switch 28 will obtain whenever the indicator hand 14, shaft 15 and control arm 32 have been displaced angularly in a counterclockwise direction, as viewed in FIG. 1, in a direction away from the zero position of the indicator hand shown in this figure.

As the control arm 32 is returned toward the zero position of the timer, the post 34 engages the center contact 30 and begins to displace it toward the contact 31 in a counterclockwise direction, as viewed in FIGS. 3 and 3A. Such displacement continues and when the zero time position is approximated, the contact 30 will have been displaced into engagement with the contact 31 as shown in FIG. 3. At the same time, however, the contact 29 follows the contact 30 and remains in engagement therewith, so that at zero time the three contacts 29, 30, and 31 are all closed or in engagement,

' as shown in FIG. 3. However, the motor 16 continues to operate, thereby maintaining the angular motion of the control arm 32 and post 34 until the center contact 30 and the contact 31 have been displaced relative to the contact 29 into the position shown in FIG. 38 at which time the contacts 29 and 30 are open and the contacts 30 and 31 closed. Such opening of the contacts 29 and 30 interrupts the energizing circuit for the motor 16 and the timing cycle terminates with the contacts 29 and 30 open and the contacts 30 and 31 closed.

At this time, the control arm 32 is in substantial abutment with the stop 35, and any tendency of the control arm 32 and shaft 15 to move in an opposite angular direction, which would tend to return the switch 28 to the position shown in FIG. 3 in which all of the contacts 29, 30, and 31 are closed, is prevented by the frictional inhibition to such movement of the control arm 32 enforced thereon by a resilient spring 36 supported by the plate 26 and oriented so as to be engaged by the control arm 32 as it moves into the zero position shown in FIG. 3. The spring 36 also tends to take out or compensate for any looseness or sloppiness in the system.

The schematic circuit diagram illustrated in FIG. 4 corresponds to the condition of the timer mechanism as shown in FIG. 3A in which the timer has been placed in operation and the indicator hand 14 and control arm 32 are being displaced toward the zero position by operation of the motor 16 and gear train 17. Thus, the contacts 29 and 30 are closed and the contacts 30 and 31 open. The circuit is intended to operate on 1 10 volt AC power obtained by connecting conductors 37 and 38 to the opposite sides of an AC source (convenience outlet) via a male plug, not shown. The circuit may also include a ground wire or conductor 39 as a protective measure.

The conductor 38 is connected to the switch contact 29, the conductor 37 is connected to the switch contact 31 via the solenoid coil 23, and the center conductor 30 of the switch 28 is connected to a conductor 40. The motor 16 and indicator lights 19 are connected in parallel between the conductors 37 and 40, and the buzzer 20 is connected in series with the alarm control switch 21 between the conductors 37 and 38. Evidently then, the motor 16 and indicator light 19 are concurrently energized or deenergized depending upon the condition of the switch 28, but the operative state of the buzzer 20 is determined by the switch 21 connected in series therewith.

In use of the timer mechanism, when the indicator hand 14 is displaced by manual manipulation of the knob 18 into the desired time-measuring position and the plunger 24 is displaced inwardly so as to open the switch 21, the circuit will have the condition shown in FIG. 4. At this time, both the motor 16 and light 19 will be energized because the circuit therefor will be completed from the conductor 37, through the contacts 30 and 29 of the switch 28, and to the conductor 38. Accordingly, the light 19 being energized will indicate that the timer is in operation. The buzzer 20 will be deenergized because the switch 21 in series therewith is open.

As time elapses, the control arm 32 and posts 34 thereof will be brought into engagement with the elongated contacts 30, and at zero time (or some other predetermined time for which the mechanism is adjusted) all three of the contacts 29, 30, and 31 will be closed, as explained hereinbefore and as illustrated in FIG. 3. When this occurs, the motor 16 and indicating light 19 will remain energized and the buzzer 20 will also become energized because closing of the switch contacts 30 and 31 establishes a circuit through the contact 30 with the conductor 38, thereby energizing the solenoid coil 23 which will displace the plunger 24 outwardly to release the contacts of the switch 21 and permit the same to close. Consequently, for the relatively brief interval that all of the contacts of the switch 28 remain closed, the motor 16, indicator light 19 and buzzer 20 will all be energized.

The period of concurrent energization of these three circuit elements depends upon the particular characteristics of the timer mechanism but, by way of example, such period approximates 3 seconds in one specific embodiment of the invention. During this 3-second interval, the control arm 32 continues to be displaced toward the stop 35 until the switch 28 assumes the position illustrated in FIG. 3B in which the contacts 30 and 31 are closed and the contacts 29 and 30 open. Whenever this condition of the switch 28 obtains, the motor 16 and indicator light 19 will become deenergized because the circuit therefor is opened by the contacts 29 and 30. The buzzer 20 will remain energized until the plunger 24 is manually returned to the inner position shown in FIG. 2 because whenever the switch 21 is closed by energization of the solenoid coil 23 it is thereafter independent of the condition of the coil 23 and, therefore, of the condition of the switch 28. Thus, the timer mechanism continues to give an audible indication'of the expiration of the time interval measured by the mechanism until it receives manual attention. Whenever the plunger 24 is displaced inwardly so as to open the switch 21, the entire circuit then becomes deenergized and remains so until the indicator hand 14, shaft 15, and control arm 32 are again displaced by manipulation of the knob 18 to start another cycle of operation.

The plunger 24 and contacts of the switch 21 may be configurated, as shown in FIG. 2, so as to latch the plunger in the switch-opening position thereof shown, thereby preventing inadvertant displacement of the plunger into its switch-closing position. The control arm 32 and/or post 34 are formed of a non-conductive material since the contacts of the switch 28 are all conductive components, although other insulating means could be used. The switches 21 and 28 may be conventional components with the spring contacts thereof formed of any usual material such as a beryllium-copper composition.

As indicated hereinbefore, the delay between energization of the second or audible signal device 20 and deenergization of the first or visual device 19 can be varied in accordance with the requirements of any particular installation. in this respect, various techniques may be employed to change the interval of such delay (i.e., the period through which both the audible and visual indicia devices are energized concurrently) such as by changing the relative spacing between the contacts 29, 30, and 31, by varying the spring bias thereof, by bending or deforming the center contacts 30 so as to change the time and extent of its engagement with the post 34, etc. In any case, the'interval during which both the audible and visual indicia are energized should be a predetermined or known quantity so that one using the timer mechanism can utilize such interval in performing the critical functions that may be related thereto.

While in the foregoing specification an embodiment of the invention has been set forth in considerable detail for purposes of making a complete disclosure thereof, it will be apparent to those skilled in the art that numerous changes may be made in such details without departing from the spirit and principles of the invention.

What is claimed is:

1. An electric timer, comprising: an electric motor; a main timing shaft drivingly connected with said motor so as to be rotatably driven thereby and being manually displaceable into angular positions of adjustment respectively corresponding to the starting points of time intervals measured from a zero time position of said shaft; an electric circuit including said motor as a component thereof, a first indicator connected in said circuit so as to be energized concurrently with said motor, a second indicator connected in said circuit and energizable in response to movement of said shaft into a predetermined angular position, control switch means having normal-run, alarm-run, and non-run conditions and including three generally parallel contacts the centermost of which is movable so as to selectively engage one or both or the other of the contacts respectively disposed along the opposite sides thereof and which engagements respectively correspond to such conditions, said control switch means and contacts thereof being connected in said circuit so that said motor and first indicator are energized only in the first two of such switch conditions and so that said second indicator is normally energized only in the latter two of such switch conditions, and a normally open alarm control switch connected in said circuit in operative association with said second indicator to control energization thereof and being responsive to said control switch means so as to be closed thereby and energize said second indicator whenever said control switch means is in the alarm-run condition thereof; and time control structure operative in enforced synchronrsm with said shaft and including an ann coactlve with the center contact of said control switch means to effect sequential staging of the latter through said normal-, alarm-, and non-run conditions thereof during a timing cycle in accordance with predetennined angular positions of said timing shaft, said center contact and one side contact being closed to define the normal-run condition of said control switch means, said arm being effective to engage said center contact and displace the same to close all three contacts and thereby define the alann-run condition of said switch means which is then maintained for a predetermined time interval during which both said first and second indicators are energized, and said arm being effective to engage said center contact and displace the same to open said one side contact while maintaining the closed condition of said center and other side contact to define the non-run condition of said switch means in which said motor and first indicator are deenergized.

2. The electric timer of claim 1 and further comprising friction means engageable with said arm as it is moved toward the zero time position of said shaft so as to resistably constrain movement of said arm and thereby obviate momentum-orginating displacements of said arm and shaft.

3. The electric timer of claim 1 in which said center contact has a projection extending beyond said side contacts, and in which said arm is equipped with a post engageable with said extension in effecting the aforementioned sequential staging of said switch means.

4. The electric timer of claim 1 in which said first indicator is a visual indicator and said second indicator is a audible indicator, and further comprising a stop engageable with said arm to define the zero time position of said shaft.

5. The electric timer of claim 1 and further comprising friction means engageable with said arm as it is moved toward the zero time position of said shaft so as to resistably constrain movement of said arm and thereby obviate momentum-orginating displacements of said arm tact has a projection extending beyond said side contacts, and in which said arm is equipped with a post engageable with said extension in effecting the aforementioned sequential staging of said switch means.

6. The electric timer of claim 5 time-calibrated face, an indicator main timing shaft so as to move said face to indicate time intervals with reference thereto, and a stop engageable by said arm to define the zero position of said shaft, and in which said first indicator is a visual indicator and said second indicator is an audible indicator.

l i I! i I! and further comprising a hand mounted upon said therewith and sweep along and shaft, said center con- 

1. An electric timer, comprising: an electric motor; a main timing shaft drivingly connected with said motor so as to be rotatably driven thereby and being manually displaceable into angular positions of adjustment respectively corresponding to the starting points of time intervals measured from a zero time position of said shaft; an electric circuit including said motor as a component thereof, a first indicator connected in said circuit so as to be energized concurrently with said motor, a second indicator connected in said circuit and energizable in response to movement of said shaft into a predetermined angular position, control switch means having normal-run, alarm-run, and non-run conditions and including three generally parallel contacts the centermost of which is movable so as to selectively engage one or both or the other of the contacts respectively disposed along the opposite sides thereof and which engagements respectively correspond to such conditions, said control switch means and contacts thereof being connected in said circuit so that said motor and first indicator are energized only in the first two of such switch conditions and so that said second indicator is normally energized only in the latter two of such switch conditions, and a normally open alarm control switch connected in said circuit in operative association with said second indicator to control energization thereof and being responsive to said control switch means so as to be closed thereby and energize said second indicator whenever said control switch means is in the alarm-run condition thereof; and time control structure operative in enforced synchronism with said shaft and including an arm coactive with the center contact of said control switch means to effect sequential staging of the latter through said normal-, alarm-, and non-run conditions thereof during a timing cycle in accordance with predetermined angular positions of said timing shaft, said center contact and one side contact being closed to define the normal-run condition of said control switch means, said arm being effective to engage said center contact and displace the same to close all three contacts and thereby define the alarm-run condition of said switch means which is then maintained for a predetermined time intervAl during which both said first and second indicators are energized, and said arm being effective to engage said center contact and displace the same to open said one side contact while maintaining the closed condition of said center and other side contact to define the non-run condition of said switch means in which said motor and first indicator are deenergized.
 2. The electric timer of claim 1 and further comprising friction means engageable with said arm as it is moved toward the zero time position of said shaft so as to resistably constrain movement of said arm and thereby obviate momentum-orginating displacements of said arm and shaft.
 3. The electric timer of claim 1 in which said center contact has a projection extending beyond said side contacts, and in which said arm is equipped with a post engageable with said extension in effecting the aforementioned sequential staging of said switch means.
 4. The electric timer of claim 1 in which said first indicator is a visual indicator and said second indicator is a audible indicator, and further comprising a stop engageable with said arm to define the zero time position of said shaft.
 5. The electric timer of claim 1 and further comprising friction means engageable with said arm as it is moved toward the zero time position of said shaft so as to resistably constrain movement of said arm and thereby obviate momentum-orginating displacements of said arm and shaft, said center contact has a projection extending beyond said side contacts, and in which said arm is equipped with a post engageable with said extension in effecting the aforementioned sequential staging of said switch means.
 6. The electric timer of claim 5 and further comprising a time-calibrated face, an indicator hand mounted upon said main timing shaft so as to move therewith and sweep along said face to indicate time intervals with reference thereto, and a stop engageable by said arm to define the zero position of said shaft, and in which said first indicator is a visual indicator and said second indicator is an audible indicator. 